Choledochal Cysts: In Brief with Dr. Alexander Bondoc

Chloidocle cysts are a congenital dilation of the biliary tree. The management of these cysts in the pediatric patient requires a keen understanding of both the anatomy and a suite of operative options. That's why today we are going to discuss the five types of colloidal cysts with an expert. In the literature there is a type 6 which is actually cystic dilation of the cystic duct itself but that's for the purposes of this discussion are probably unnecessary. That's Dr. Alexander Bondock. He's a pediatric transplant surgeon at Cincinnati Children's Hospital and today he's going to walk us through everything you need to know about the workup and management of Chloidocle cysts in children. Some of the operative reconstructions can get a little tricky so be sure to watch in the Stay Current app. We have all of the images posted below the media player so that you can follow along. Chloidocle cyst is a core pathology in pediatric surgery and it does have a female predominance but the main difference in diagnostic incidence is where you are in the world. In the Western world it's about the incidence is about one in 100,000 but in Asia specifically Eastern Asia it's actually a little quite more quite a bit more common one in 13,000. When categorizing colloidal cysts most commonly we refer to the Todani classification and that's types one through five. These categories describe the location of the cysts and they give hints to the underlying pathophysiology. Types one and four it is likely embryologic relating to the pancreatic obiliary duct junction also known as in this scenario pancreatic obiliary malunion. Now keep in mind that pancreatic obiliary malunion is just one theory for the etiology of colidocle cysts. It's not a slam dunk not even for Todani types one and four and it doesn't really explain why there's a higher incidence in the Far East. There's probably something else going on like a congenital proliferation. Now in adults that common channel are basically the confluence of the biliary pancreatic ducts. It's supposed to be less than 0.9 centimeters but in the pediatric patient any common channel is abnormal and that is the cause for a lot of these issues. Reflux of pancreatic enzymes from obviously the head of the pancreas back into the biliary tree causes inflammation, degeneration and epithelial changes. No genetic syndromes include colidocal cysts but a type 5 cyst otherwise known as Carolli's disease does have an associated genetic gene mutation and PKD1. In type 5 as mentioned previously the genetic mutation might predispose to more diffuse dilation of both the intra and extrahepatic biliary trees. Let's dive into the Todani classification of these cysts. Don't worry, a chart with all these images is linked below the media player. Type 1 is a dilation of the common bile duct only, the extrahepatic common bile duct only and that can either be fusiform or saccular. Type 2, colidocal cyst is just a small diverticulum off of the common bile duct. Type 3 or a colidocal seal is a dilation of the common bile duct in the wall of the duodenum. Type 4 is divided into two types. Type 4a which is a multitude of cysts both in the intra and extrahepatic biliary tree as well as and type 4b are multiple cysts but in the extrahepatic biliary tree only. Type 5 otherwise known as Carolli's disease has diffuse cystic dilation. This can be diffusely throughout or it can be limited to one lobe of one heavy liver. Now that we know how to refer to these cysts discovery is key. The presenting symptoms depend on the age of presentation. Oftentimes in younger children such as infants it's diagnosed incidentally on axial imaging or ultrasound imaging for other causes. In children oftentimes you will get symptoms consistent with cholangitis such as jaundice or fever. The patients also can have a palpable right upper quadrant mass. This sounds suspiciously like Charcot's triad which means we could have a pretty sick kid on our hands. Luckily this is a fairly uncommon presentation. Also uncommon but disconcerting is the idea of cystic perforation as a presenting symptom. Giant cysts that children are born with can actually perforate and present with biliary ascites. These large colloidal cysts can be identified on a 20-week fetal ultrasound and those are best referred to a fetal center for workup and close monitoring after birth. We need to be on the lookout for postnatal perforation and for a particular biliary atresia variant. That's something you don't want to miss. There was a recent citation that demonstrated that if a cyst was diagnosed prenatally and it was larger than four and a half centimeters at the 20-week anatomy scan there was a higher rate of postnatal symptomatology and the authors therefore made the conclusion that perhaps these patients may benefit from earlier intervention. In all children the differential diagnosis for jaundice should include colloidal cysts in addition to other gallstone disease. The workup is fairly standard for biliary pathology. Lab standpoint again with special attention to the patient's age labs to check would be liver function tests specifically with total direct and indirect bilirubin levels as well as plus minus a CBC to look for evidence of cholangitis or infection. These labs plus an abdominal ultrasound can be diagnostic however in infants we also really need a liver biopsy. Liver biopsy does become critical if you're talking about a neonate or a newborn because again as men as we discussed earlier you have to rule out the cystic biliary atresia variant. Cannot miss that. While an ultrasound and labs are all we need to diagnose a colloidal cyst, axial imaging such as a CT scan is needed before taking these kids to the operating room. Additionally there are some cases where an MRCP may be useful for operative planning. If there are questions about anatomic details specifically I like to use an MRCP if there's high disease meaning disease that's into the hilum or intra hepatic to sort of get a better sense of how extensive the the cystic change is. Got it got it. Okay so MRCP would be helpful to identify that variant biliary anatomy. Probably up to 15 to 20 percent of patients have some kind of variant biliary tract anatomy. Axial imaging is useful preoperatively and these images can identify when an ERCP can be both therapeutic and diagnostic. From a diagnostic and therapeutic standpoint some patients will benefit from an ERCP but again that oftentimes depends on what you see from prior scans as well as the type of colloidal cyst you're dealing with. Let's say I have a patient who comes in with jaundice and a palpable right upper quadrant mass. We get the labs, we get the imaging and I diagnose a colloidal cyst. Surgery is really the only true treatment option. Both to correct the the What you're trying to prevent when you have anatomic anomalies of the biliary tract one significant complication that can occur is cholangitis. If you have biliary stasis you get super infection you end up these patients are prone to cholangitis. So we want to reduce the risk of biliary cirrhosis and hepatic failure but the really pressing concern is the risk for developing cholangiocarcinoma which according to some studies can be as high as 26 percent. Even after surgical resection of these cysts there some studies suggest that there is still about a four percent lifetime risk of malignancy which means that these patients need to be surveilled through their life. Patients presenting acutely can have pancreatitis or cholangitis. Infection inflammation in the pancreatic biliary tree can make for a hostile surgical field. And you know what they say. Don't mess with the pancreas. Patients presenting acutely can also treat their underlying patient patients as well. If the lesion is found incidentally resection is not really an emergency but it is better to schedule surgery sooner rather than later. Incidentally, resection is not really an emergency, but it is better to schedule surgery sooner rather than later. But that gives you ample opportunity to gather all of the necessary preoperative evaluation. The workup includes a basic set of laboratory values. Preoperative imaging, which is most likely an MRCP. And evaluation to ensure that there's no other disease process occurring. For example, we definitely do not want to miss cystic biliary atresia. Now one thing you could do is you could just verify that the baby is having pigmented stools. The surgical approach for colloidal cysts really depends on the type, but the overall goal is the same, a complete excision of cystic elements. Type 1 and type 4, because of what we discussed regarding the anomalies of the pancreatic obiliary anatomy, the goals here are to remove as much of the duct as possible. And when I say that, that oftentimes, that always takes you behind the head of the pancreas or into the head of the pancreas, because the key here is to take the duct all the way down to where it tapers into very little. So as not to leave remnants cysts. Usually the preoperative MRCP is enough to tell you where that taper behind the pancreas is hiding. But if the imaging isn't totally clear, you're not exactly sure, or there's some really aberrant anatomy, you have another option that is rarely used, but you could do an intraoperative cholangiogram. Through the gallbladder, so that I try to truly understand where the tapering of the distal cyst occurs, so that we're not leaving anything extra. Reconstruction can include a hepaticoduodenostomy, or Dr. Bondock's preference, a hepaticojejunostomy. For type 1 and type 4 cysts, you also have to reconstruct the biliary drainage system. Oftentimes this will include a Roux-en-Y hepaticojejunostomy, but a hepaticoduodenostomy is also an option and has been described. Scroll down below the media player. That's where we have animations to further detail the typical Roux-en-Y hepaticojejunostomy reconstruction and the normal two anastomoses. Once the cyst is resected, then we work towards reconstructing the biliary outflow. I personally like to do Roux-en-Y hepaticojejunostomies. The way I construct those in my practice is I usually go about 15 to 20 centimeters distal from the ligament of trites or whatever you think will be comfortable and allow reach of the Roux-en-Y hepaticojejunostomy. Then perform a jejunojejunostomy if the child allows it, if the child size allows it in two layers, and then do a hepaticojejunostomy with interrupted absorbable suture, usually 5-0 or 6-0 maxon. This reconstruction does leave a defect in the small bowel mesentery. Depending on the size, some surgeons may choose to leave the defect alone, but others will close it to prevent complications related to internal hernias later on. I don't usually biopsy the liver unless there's something obvious, but I do close the mesentery. Type 2 choleodoclesis require a resection of the diverticulum and a primary repair of the common bile duct. Type 3, now that is where ERCP and sphincterotomy can be therapeutic in some cases, but sometimes it's just not that easy. If the lesion is large and obstructing the common duct, you oftentimes have to go transduodenal and carefully identify, sometimes even with preoperative stents that can be inserted from an ERCP standpoint, in order to resect the cyst separated from the duodenum and subsequently reconstruct the outflow. Type 5 requires a little more workup to determine the best operation to achieve complete cystic resection. And that may even require a liver transplant. If the cystic burden is limited to one side of the hemi liver or would allow for resection and residual adequate liver remnant, as well as preserved biliary outflow, you can address it surgically with a liver resection. However, if the cystic disease is diffuse and throughout the liver, you may have to consider having that patient evaluated for liver transplantation. The good news is postoperatively, these patients do really well. They have an NG tube for about 24 hours to protect that new jejunal anastomosis and they have temporary biliary drains until they're eating a regular diet. So you can catch any leaks from that hepaticojejunostomy. Otherwise, the postoperative complications are pretty standard for any abdominal operation. They do have an additional risk for recurrent cholangitis due to the connection between the biliary tree and the enteric system. Certain even short-term to long-term surgical complications can include an anastomotic stricture, small bowel obstruction from intra-abdominal surgery, as well as reflux gastritis. Other things that can occur, as discussed above, would be recurrent cholangitis due to having a direct connection between the biliary tree and the enteric system. Prophylactically, patients are put on Bactrim. Act of all can also be helpful postoperatively, but that may be more institution-specific. Most importantly, these kids grow up and they need long-term follow-up. That is critical. The need for lifelong follow-up for these patients because of the possibility of developing, well, albeit small, the thought is there still is a very real possibility for future malignancy, even after resection of the cyst itself. Thanks for joining us for a review of colloidal cysts and the myriad of surgical options based on the Todani classification. Remember to check the link below for access to the entire lecture and all the images that we discussed in this episode. Follow us on social media, like and subscribe to our YouTube channel, check us out on Twitter or wherever you listen to your podcasts. If you're listening, leave a comment below. Tell us what you like, what you didn't like, what you want to hear more of in the future. Until then, this is Brittany and remember, knowledge should be free.